You have set your ConnectionInfo to blank.
You need to set the Server, Database, User & Password or Integrated Security to true.
The following code is what I use when I create the ConnectionInfo;
ConnectionInfo crConn = new ConnectionInfo();
crConn.Servername = "myServerName";
crConn.DatabaseName = "myDbName";
crConn.IntegratedSecurity = false;
crConn.UserID = "muUserName";
crConn.Password = "myPassword";
ReportDocument rptDoc = new ReportDocument();
rptDoc.Load("myPath");
Tables rptTables = rptDoc.Database.Tables;
for(int i = 0; i < rptTables.Count; i++)
{
Table rptTbl = rptTables[i];
TableLogOnInfo tblInfo = tblRpt.LogOnInfo;
tblInfo.ConnectionInfo = crConn;
tblInfo.ApplyLogOnInfo(tblInfo);
}
If Sub Reports exist you need to do the same for each Table in each Sub Report
Kind Regards